Results 21 to 30 of about 17,890 (211)
In this research, a metal-free diastereoselective formal 1,3-dipolar cycloaddition of N-2,2,2-trifluoroethylisatin ketimines and cyclopentene-1,3-diones which can efficiently lead to the desymmetrization of cyclopentene-1,3-diones is developed.
Lin-Qiang Li +7 more
doaj +1 more source
An expedient synthesis of hitherto unexplored novel hybrid heterocycles comprising dispiropyrrolidine, N-styrylpiperidone and indeno[1,2-b]quinoxaline units has been developed via domino multicomponent 1,3-dipolar cycloaddition strategy employing a new ...
Abdulrahman I. Almansour +8 more
doaj +1 more source
Synthesis of pyrrolizines by intramolecular capture of 1,4-dipolar intermediates in reactions of enamines with dimethyl acetylenedicarboxylate [PDF]
Solvent polarity and reaction temperature strongly influence the reactions of dimethyl acetylenedicar-boxylate (DMAD) with 1-pyrrolidinyl enamines of acyclic and cyclic ketones. Whereas DMAD and 1-[1-phenyl-2-(phenylthio)ethenyl]pyrrolidine (3) give only
Harkema, S. +5 more
core +3 more sources
1,3-Dipolar Cycloadditions of N-Benzyl Furfuryl Nitrones with Electron-rich Alkenes
The 1,3-dipolar cycloaddition reaction of N-benzyl-C-(2-furyl)nitrones with electron-rich alkenes gives preferentially trans-substituted 3,5-disubstituted isoxazolidines (endo approach).
Tomas Tejero +3 more
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Büchwald-Hartwig reaction applied to synthesis of new luminescent liquid crystal triarylamines derived from isoxazoles [PDF]
© 2015 Taylor & Francis Group, LLC. The present work describes the synthesis and characterization of novel series of triarylamines isoxazoles (TAA) addressed to the organic photovoltaic materials. Diarylisoxazoles were synthesized by sequential [3+2] 1,
Fernandes, T. H. M. +3 more
core +2 more sources
Hydrophilic Janus Micelles From an ABC Triblock Copolymer
An amphiphilic triblock copolymer with poly(ethylene glycol) (PEG) and poly(N‐vinylpyrrolidone) (PVP) coronas self‐assembles into spherical micelles with Janus‐type surface segregation in water. Cryo‐TEM, enabled by selective PVP labeling, and 1H‐NOESY NMR reveal phase separation.
José Muñoz‐López +5 more
wiley +2 more sources
Diastereoselective reactions between 4-formylpyrazoles, N-substituted maleimides and glycine derivates led to new series of pyrazolyldipyrrolo [3,4-a:3',4'-f]pyrrolizines and pyrazolylpyrrolo[3,4-c]pyrroles in good yields.
Jairo Quiroga +6 more
doaj +1 more source
Copper(I)-Phosphinite Complexes in Click Cycloadditions: Three-Component Reactions and Preparation of 5-Iodotriazoles [PDF]
© 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.The remarkable activity displayed by copper(I)–phosphinite complexes of general formula [CuBr(L)] in two challenging cycloadditions is reported: a) the one-pot azidonation/cycloaddition of
Crosbie, P +3 more
core +3 more sources
It may seem counterintuitive to first target a ruthenium alkylidyne when Grubbs‐type ruthenium carbene complexes are the actual goal. In the end, however, this tactic pays valuable dividends in terms of practicality, atom economy, flexibility as well as safety: the new route provides ready access to a large assortment of catalysts for alkene metathesis
Mingxu Cui, Alois Fürstner
wiley +2 more sources
Diethyl 4-acetyl-5-(2-nitrophenyl)pyrrolidine-2,2-dicarboxylate
The title compound, C18H22N2O7, was synthesized by the 1,3-dipolar cycloaddition reaction of but-3-en-2-one, diethyl 2-aminomalonate and 2-nitrobenzaldehyde. In the molecule, the pyrrolidine ring possesses an envelope conformation.
Long He
doaj +1 more source

